GSM Network Architecture GSM Architecture Numbering and Routing GSM Services Engr. Mian Shahzad Iqbal Lecturer Department of Telecommunication Engineering Introduction Global System for Mobile Communication (GSM) Anybody – 500 million users (may 2001) Anywhere – 168 countries (may 2001) Any media – voice, messaging, data, multimedia Source: Hillebrand, 1 GSM Architecture Home Location Register BTS = Base Transceiver Station AuC Network Management Center AuC = Authentication Center OMC = Operation and Maintenance Center Equipment ID PSTN = Public Switched Telephone Network ME = Mobile Equipment Subscriber Identity Module ME B T S Subscriber Identity Module ME B T S Subscriber Identity Module ME B T S Visitor Location Register Mobile switching center Base station controller OMC Data communication network PSTN Source: Stallings, 313 Source: Mehrotra, 27 GSM Architecture MS Transmission Band : 890 – 915 MHZ BS Transmission Band : 935 – 960 MHZ 45 MHz F1 F2 F1' F2' 1 2 3 4 5 6 7 8 Year Introduced 1990 Access method TDMA Channel Bandwidth 200 kHz Number of duplex channels 125 Users per channel 8 Speech coding bit rate 13 kbps Data coding bit rate 12 kbps Frame size 4.6 ms Frequency SIM (Subscriber Identity Module) Billions of Calls Millions of Subscribers Thousand of Different Types of Telephones Hundreds of Countries Dozens of Manufacturers…. •Administrative data And only one Card: The SIM •Security data •Subscriber data •Roaming data •PLMN (Public Land Mobile Network Source: Hillebrand, 369 http://ucables.com/products/simcards/ Subscriber Identity Module (SIM) Subscriber Identity Module Contains phone number (MSISDN) international mobile subscriber identity (IMSI) status of SIM service code authentication key PIN (personal identification code) PUK (personal unlock code) SIM Cards SIM cards are embedded with a microprocessor Stores customer identity information and is made to fit inside the cellular phone Memory capacity 1K, 3K, 8K, 16K,32K,64K Mobile Station Mobile Station = SIM Card Handset Battery Global GSM Mobility Card The Smart Card to use GSM battery + + f153454 2W jmhfod kgdjipj SIM-Card and GSM Mobile Equipment SIM-Card Global GSM Mobility Card = The Smart Card to use + Calling line 0609225831 GSM Contains: - IMSI Subscriber knows Called party number = MS-ISDNPIN Handset The SIM-Card Functions Credit Card Size µ SIM-Card Global GSM Mobility Card 15 mm The Smart Card to use 25 mm Permanent data: - Unique mobile subscriber identity through IMSI number, - Authentication parameter Ki, - Authentication algorithm A3, - Generating encryption key Kc algorithm A8. GSM Microchip with stored user information Removable data: - Temporary Mobile Subscriber Number, - Location Area Identification. Subscriber Identification IMSI Nature International Mobile Subscriber Identity Mobile Station Integrated Services Digital Network Nb Conformity with E212 Similar to ISDN, Conformity with E164/E213 Identify a PLMN worldwide MCC MNC Meaning Mobile Country Code Mobile Network Code Nb. digits 3 2 Format MS - ISDN Identify the subscriber of a PLMN MSIN H1 H2 x x x ......... x x x Mobile Subscriber Ident. Nb H1 H2 = Identity of HLR within the home PLMN max 10 National Significant Mobile Number CC NDC SN M1 M2 xx xx xx xx Country National Mobile Subscriber Code (where Destination (national definition) subscription Code * M1 M2 = nbr of logical HLR has been made) 1 to 3 2 to 4 total max 15 *This code does not identify a geographical area but an operator MS Classmark Classmark Power classes Revision level (Phase 1, 2, 2+) RF power Encryption algorithm (A5/1,A5/2) Frequency (900/1800/1900) Short message Class GSM 900 1 2 8 W* 3 5W 4 2 W** 5 * ** GSM 1800 GSM 1900 1 W** 1 W** 0.25 W 0.25 W 4W 4W 0.8 W Typical value for car mounted Typical value for handheld MS (Mobile Station) ME (Mobile Equipment) ADVANTAGES OF GSM Digital Global Noise Robust Open Interfaes Secure NETWORK ARCHITECTURE OMS Operations & Maintenance Subsystem NSS Network Switching Subsystem MS Mobile Station BSS Base Station Subsystem BSS (Base Station Subsystem) BSS Connectivity NSS (Network Switching Subsystem) OMS (Operations & Maintenance Subsystem) The Network In Reality GSM Network Elements Handset BTS: Base Transceiver Station MSC: Mobile Switching Center BSC: Base Station Controller HLR/VLR: Home Location Register/Visiting Location Register SIM Card: Subscriber Identity Module Card Service Centers: USSD, SMS, ... Base Transceiver Station (BTS) / Base Station Responsible for communication to and from MHs via air interface MS communicates with the mobile system using a radio channel to a BTS BTS comprises radio transmission and reception devices Including the antennae and signaling processing specific to the radio interface BTS separates the speech and control signaling associated with a MS and sends them to the BSC on separate channels Mobile services Switching Center (MSC) Responsible for all switching functions related to call processing Coordinate the setting up of calls to and from GSM users MSC is the interface between GSM network & PSTN (Public Switched Telephone Network) Gateway MSC (G-MSC) • The MSC with an interface to other networks is called GMSC. • Network operator may equip all there MSCs with gateway function or only few. • MSC that don’t have gateway function has to route call from GMSC. • GMSC has some additional tasks like call from outer network enters in GMSC which queries HLR then forwarded the call to MSC where the called party is located. Base Station Controller (BSC) Monitor and Control several base stations Frequency administration, control of BTSs, exchange functions Responsible for all the radio interface management Channel allocation and release, handover management BSC is the interface between MSC and BTS BSC is connected on one side to several BTSs and on the other side to the MSC Home Location Register (HLR) A database in charge of the management of mobile subscribers Contains information of network subscribers Information on teleservices and bearer services subscription, service restrictions, and supplementary services The data stored in HLR is of a semi permanent nature and does not usually change from call to call Visitor Location Register (VLR) Contains the relevant data of all MSs currently located in a serving MSC The permanent data is the same as data in the HLR The temporary data includes Temporary Subscriber Identity (TMSI) Location Area Identity (LAI) of an MS VLR allocates mobile subscriber roaming numbers (MSRNs) for the incoming call setup The relation between MSC and VLR • Sum of MSC areas determine the geographical area of any PLMN. • Each MSC has its own VLR so PLMN can also be described as the sum of all VLR areas. • VLR can serve several MSC but one MSC always use only one VLR. Equipment identity register (EIR) • The separation of subscriber identity from the identifier of MS also bears a potential pitfall for GSM subscribers. • It is possible to operate any GSM MS with any valid GSM SIM. An opportunity exists for black market and stolen equipment. • To combat this problem EIR is introduced to identify and track such equipment. EIR (cont) • Each GSM phone has a unique identifier IMEI which can not be altered. • Like HLR and VLR, the EIR is also a data base which maintain three lists. EIR (cont) • The processes of mobile equipment fallen dramatically due to great success of GSM consequently the theft rate reduced. So several GSM operators have decided not to install the EIR. • If the EIR is installed there is no specification when the EIR should be interrogated. The EIR may be interrogated any time during call setup or during location update. Transcoding rate and adaptation unit. (TRAU) • One of the most interesting features of GSM is TRAU. Its function is the compress and decompress the speech between TRAU and MS. Possible location are as below. Geographical Network Structure Location Units Cell Location Area (LA) MSC/VLR Service Area PLMN (Public Land Mobile Network) Service Area GSM Service Area Cell Planning Location Information -GSM Service Area Hierarchy The area in which a subscribe r can access the network. GSM Service Area PLMN Service Area (one per operator) MSC/VLR Location Area cell Numbering & Routing Numbering Mobile Subscriber ISDN Number (MSISDN) Mapping to Mobile Station Roaming Number (MSRN) by HLR International Mobile Subscriber Identify (IMSI) Stored in SIM/HLR Temporary Mobile Subscriber Identity (TMSI) Assigned by VLR, Stored in VLR International Mobile Equipment Identity (IMEI) Unique ID to handset, used by air interface ID-Numbers MSISDN = CC + NDC + SN MSISDN: Mobile Station ISDN Number CC Country Code NDC National Destination Code SN Subscriber Number IMSI = MCC + MNC + MSIN IMSI MCC MNC MSIN International Mobile Subscriber Identity Mobile Country Code Mobile Network Code Mobile Station Identification Number ID-Numbers (cont.) IMEI = TAC + FAC + SNR + spare IMEI Internal Mobile Equipment Identity TAC Type Approval Code, determined by a central GSM/PCS body FAC Final Assembly Code, identifies the manufacturer SNR Serial Number, uniquely identifies all equipment within each TAC and FAC IMEISV = TAC + FAC + SNR + SVN IMEISV International Mobile Equipment Identity and Software Version Number SVN Software Version Number ID-Numbers (cont.) MSRN = CC + NDC + SN MSRN Mobile Station Roaming Number CC Country Code NDC National Destination Code SN Subscriber Number. In this case, the address to the serving MSC LAI = MCC + MNC + LAC MCC MNC LAC Mobile Country Code Mobile Network Code Location Area Code ID-Numbers (cont.) CGI = MCC + MNC + LAC + CI CGI CI Cell Global Identity Cell Identity BSIC = NCC + BCC BSIC NCC BCC Base Station Identity Code Network Color Code (3bits) Base Station Color Code (3bits) LN = CC + NCD + LSP LN CC NCD LSP Location Number Country Code National Destination Code Locally Significant Part ID -Numbers (cont.) LN = CC + NCD + LSP LN CC NCD LSP Location Number Country Code National Destination Code Locally Significant Part RSZI = CC + NDC + ZC RSZI CC NDC ZC Regional Subscription Zone Identity Country Code National Destination Code length of the Zone code (2 octets) Routing Information resident in MS & SIM IMSI, TMSI, IMEI, and misc. information Routing Information used by Network MSISDN, MSRN GSM Services and Features 1. Tele Services 2. Bearer Services or Data Services 3. Supplementary Services Teleservices 1 - Telephony Hello Speaking Originated call 1 Speaking Hello Terminated call 1 Teleservices 2 - Emergency Call Global GSM Mobility Card The Smart Card to use GSM Do not require a SIM-Card while "112" is invoked Emergency 112 Teleservices 3 - Short Message Cell Broadcast me ssa ge A ge A a s s me me ssa ge B e sag s e m Information Provider A A B age s s me ge a s es m s es m me s s age B B e ag Information Provider B A GSM Network Teleservices 4 - Short Message Service Radio SMS-MO/ PP PLMN SMS-SC Radio PLMN SMS-MT/ PP Copyright © 1996 Northern Telecom Teleservices Alternate Speech and Fax: 5 - Fax Automatic fax: Teleservices Embodied bearer treatments for radio transmission 6 - User's Data Call Features Teleservices voice Teleservices Fax G3, SMS Cable that bears data Data / Fax kit adaptation Teleservices Please leave a message after the tone Busy 7 - Voice Messaging Forward to voice mail box 1 Voice mail box GSM network You have 3 voices messages... Retrieving the voice messages Warming up... Voice message server Bearer Services Limited to 1,2 and 3 OSI layer Packet Switched Protocols Data Rates from 300bps to 9.6kbps Supplementary Services Calling Party CoLP CLIR Calling Line Identification 1 - Line Identification Cnted line 0609173957 presentation (CLIP) restriction (CLIR) Connected Line Identification presentation (CoLP) restriction (CoLR) Calling Name Presentation (CNAP) Called Party CLIP CoLR Calling line 0609225831 Supplementary Services 2 - Call Transfer and Call Forwarding unconditional (CFU) on busy (CFB) on no reply (CFNRy) on not reachable (CFNRc) 1 2 Supplementary Services 3 - Waiting / Hold and Multi Party WAIT 1 HOLD 2 1 2 Waiting / Hold: 1 Multi Party: 1 Max = 5 persons 2 2 Supplementary Services 4 - Call Barring z Outgoing (BAOC) z Outgoing international (BOIC) z Outgoing international except home PLMN country (BOIC-exHC) z Incoming (BAIC) z Incoming when roaming outside (BIC-Roam) Supplementary Services 5 - Call Completion (CCBS) NEW ! BUSY ... Unable to place a call. Speaking 1 2 This call in state Reinitiate the call Ring ! Ring ! 1 Idle SPEAKING Call is established HELLO 1 Speaking Supplementary Services Advice of Charge Information (AoCI) 6 - Advice of Charge information on progress of the cost of the call Advice of Charge Charging (AoCC) Insert a SIM credit Card Completion of call need charging Intelligent Network Services Main IN Services: IN and CAMEL Personal Number Virtual Private Network (VPN) Sponsored Cell & Call Prepaid Calling Location Inquiry Geo Zone The aim of the CAMEL (Customized Application for Mobile network Enhanced Logic) is to provide GSM network operators with the ability to create specific services in their home network, and export these services to their subscribers when roaming outside the home network. CAMEL introduces the ability to provide location dependent IN type of services to mobiles subscribers. IN Services: Virtual Private Network 25 c/min 5696 Closed User Group c 1 4 7 Location & Time dependant screening 2 5 8 o+ X Copyright © 1996 Northern Telecom Copyright © 1996 Northern Telecom X 3 6 9 * ** 4197 0 # 7PRS8TUV9WXY GHI 4 5JKL 6MNO 1 2ABC3DEF Copyright © 1996 Northern Telecom Corporate Numbering Plan 4446 25 c/min Wireline Access Lower rate for on-net calls 4197 c 1 4 7 London * Bristol 2 5 8 o+ 3 6 9 Copyright © 1996 Northern Telecom Location & Time dependant routing 25 c/min 5696 4446 Speed Dialing 50 c/min 924 63256 Copyright © 1996 Northern Telecom Copyright © 1996 Northern Telecom Copyright © 1996 Northern Telecom Las cos t call 0.50ts $ New bala $ 24 nce is .50 5542 1139 1464 228 99494 VALID DATES 6/91 6/99 SCOOBY DOO Your account balance is $ 24.50 Copyright © 1996 Northern Telecom Multiple recharging options Account status enquiry and notification Multiple Tariff Plans Tariffs using fixed charge, CC, NC, distance, time & day, roaming charges... Possible language selection by subscriber Flexible features for easy Bulk account loading for easy provisioning service packaging Copyright © 1996 Northern Telecom RANK1ONE Copyright © 1996 Northern Telecom IN Services: Prepaid Calling IN Services: Location Inquiry The closest restaurants are: The Wind Jammer on 132 Flinton Street Sea food Phone 55 1968 press 1 to connect Copyright © 1996 Northern Telecom The Palace on 11 Bourke Street Chinese food Phone 55 0407 press 2 to connect Promotional Information s: call #15 Cell dependent information Direct connection to advertisers Today’s special at The Anchor is Maine lobster soup Be the first ten caller and get a free cocktail ! Copyright © 1996 Northern Telecom The Anchor St Catherine Dock Phonce 56 2548 Press 2 to connect Copyright © 1996 Northern Telecom The closest restaurants are: The Tower, Tower Hill, Phone 56 4589, Press 1 to connect Possible customization of announcement directly by the advertiser Q&A?
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project